nixvimConfig/overlays/default.nix

{inputs, ...}: {
  nixpkgs.overlays = [
    (final: prev: import ../pkgs final.pkgs)

    # Any custom modifications
    # https://nixos.wiki/wiki/Overlays
    (final: prev: {
      nixvim = builtins.trace "foobarzelidumm" inputs.nixvim-config.packages.${prev.system}.default;
    })
    # example = prev.example.overrideAttrs (oldAttrs: rec {
    # ...
    # });
  ];
}